A Groundwater Vulnerability Assessment Of The Greater Pietermaritzburg Region Using Drastic In A Gis Environment
This study, near Thyspunt between St. Francis and Oyster Bay in the Eastern Cape Province of South Africa, focused on identification and quantification of surface water–groundwater links between the mobile Oyster Bay dune field and the coast. The specific objective was to establish the extent to which important wetlands such as the Langefonteinvlei and the numerous coastal seeps along the coast are directly or indirectly dependent on groundwater as their main water source.
One of the critical elements of water resource management is the dynamic exchange between groundwater and surface water. Quantifying this exchange strongly relies on an adequate characterisation of the lithological architecture of the involved aquifer system. In the past, this characterisation often relied on lithological data obtained through invasive methods.
The Karoo Supergroup has a hydrogeological regime which is largely controlled by Jurassic dolerite dyke and sill complexes. The study area is located in the north-eastern interior of the Eastern Cape Province, close to the Lesotho border. The sedimentary rocks of the upper Karoo constitute fractured and intergranular aquifers, due to relatively hydro-conductive lithologies.
Lake Kosi Bay is an estuary-linked lake system composed of four interconnected lakes, namely Makhawulani , Mpungwini , Nhlange , Amanzamnyama and interconnecting channels, which drains via a sandy opening to the Indian ocean and three extensive areas of swamps (Wright 2002 ). The Kosi Bay lake system is considered as the most pristine lake system on the South African coast and has been used as a recreational fishing destination since 1950 (James et al. 2001).
The study focuses on the primary aquifer in the Cedarville flats. Groundwater extracted from the aquifer is the primary source for domestic and agricultural purposes for farmers and the community in the Cedarville area. The aim of the study is to develop a conceptual hydrogeological model of the primary aquifer in Cedarville flats which may be used as an input to a groundwater flow model that will predict the behaviour of the aquifer. The main objectives of the research are:
Groundwater is a reliable freshwater resource. Its location underground prevents it from evaporative forces. Thus it serves as storage of most of the world’s liquid fresh water. Being enclosed in the ground it is not also easily contaminated. Since groundwater can be used wherever it exists without costly treatments, there is over-dependence on the resource.
Groundwater is the water that is found beneath the surface of the ground in a saturated zone (Bear 1979). Groundwater contamination refers to the groundwater that has been polluted commonly by human activities to the extent that it has higher concentrations of dissolved or suspended constituents. The scale of the potential supply of groundwater from the Cape Flats Aquifer Unit (CFAU) is very significant due to the increase of the population in Cape Town that leads to limited water resources (Maclear 1995).
Groundwater in South Africa is an essential source of potable water for rural communities, farms and towns. Semi-arid conditions of South Africa, a growing population and surface water resources almost entirely being exploited to their limits, increase the demand for groundwater resources. Therefore, the relation between the geology and geohydrology of South Africa becomes an important tool in locating groundwater resources that can provide sustainable quantities of water for South Africans.
© Copyright Ground water division 2021 All rights reserved. | Build by WebBest